Motion limitation means for enhanced-function flush handles

Abstract

A toilet flusher comprising an exterior flush handle and a means for limiting the flush handle's rotation, the means being located entirely within the toilet tank. The means involve both the rear planar as well as the side cylindrical walls of the spud, in order to enhance the spud's strength and rigidity. The means further comprise a bent lift arm within the tank, and a motion limitation hub on the lift arm. The hub is sufficiently distant from the bend of the lift arm that conventional attachment of the toilet flusher to the front wall of a toilet tank, by passing the conventional left-handed nut over the entire visible length of the lift arm, including over the motion limitation hub, and onto the threads of the spud, may be easily accomplished. This is particularly advantageous for enhanced-function flush handles that are designed to be connected removably to the remainder of the toilet flusher and that will thus typically lack space within their housings to accommodate the usual, motion limitation means. The present invention allows an enhanced-function flush handle to be located as close to a tank as a conventional flush handle, and thus to accommodate more easily those installations where, for whatever reason, the tank lids are missing or slip backwards easily when the seats are leaned back against the lids.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

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STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

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REFERENCE TO A MICROFICHE APPENDIX

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SEQUENCE LISTING

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BACKGROUND OF THE INVENTION

This invention relates to enhanced-function flush handles installed on conventional, North American toilets, in particular to the mechanical means that limit such flush handles' motion, most importantly their rotation, within the coaxial spuds and nuts that attach them to their respective toilet tanks. An enhanced-function flush handle—one example of which is the Flush Handle Night Light (marketed as the Flush Light™ and first disclosed in U.S. Pat. No. 6,231,203 to Olshausen (2001), and further developed in U.S. patent application Ser. No. 10/967,227, filed Oct. 19, 2004)—delivers a benefit—e.g., illuminates a toilet bowl, dispenses a fragrance, says “thank you” in a parent's recorded voice during potty training, etc.—supplementary to the plumbing function of a conventional flush handle. A spud is the shouldered, left-hand threaded component that extends through the square aperture in the front wall of a conventional toilet tank and that is firmly but removably attached to the tank with a left-hand threaded nut. A lift arm extends into the tank from the spud and is either removably, or else permanently, attached to an external flush handle. Contemporary, conventional flush handles are almost always permanently attached to their lift arms, typically by glue for plastic lift arms and by a press fit for metal flush handles. An enhanced function flush handle such as the Flush Light™ will, on the other hand, typically be removably attached to its lift arm by means of an intermediary element, termed a tenon in U.S. patent application Ser. No. 10/967,227, op. Cit. A shank on the lift arm is cemented into a socket in the tenon, thus permanently and rigidly attaching tenon and lift arm. The shank of the lift arm and the socket of the tenon then move freely together within the spud, principally by rotating within it, although there will also be some slight, translational play along the axis of rotation as well. When a flush handle, either conventional or enhanced-function, is pressed down upon by a hand in the usual manner to flush a toilet, the flush handle rotates counterclockwise (as seen by the user) through an acute angle. The lift arm rotates with it, thereby causing a water valve inside the tank to open, commencing flushing.

Both enhanced-function as well as ordinary flush handles are limited in their ability to move, particularly to rotate. Most important is their limitation on clockwise rotation. The reason is that the flush handle, when not in use, must continually remain available for a counterclockwise, i.e., for a flushing, rotation, and yet each time to achieve best results must begin from a horizontal position. An initial, horizontal position converts a downward impulse applied by hand into a counterclockwise, i.e., flushing, rotation of the flush handle and the lift arm rigidly attached to the flush handle more efficiently than any other initial orientation. To keep the flush handle, which by itself exerts a counterclockwise torque, horizontal, a greater and opposing torque, namely, a clockwise torque, must be exerted by the lift arm. However, actual clockwise rotation must be limited such that the flush handle always returns to rest in a horizontal position.

A great many means, some of them entertainingly complex (e.g., U.S. Pat. No. 977,122 to Newton (1910)), have been patented, for limiting flush handle rotation. Generally, the contemporary, conventional means are all located external to the toilet tank, and typically involve some structure of the spud so disposed that this structure will block the rotation of two other structures located within the flush handle, one each at the opposite ends of the range of rotation. Such external, motion limitation means are found both in contemporary, conventional flush handles and in the Flush Light™, at least through the Flush Light's™ development in 10/967,227, op. Cit. But the disadvantage of such external means for limiting motion is, that the flush handle must either have space available within itself for at least some of the necessary structures, or else the distance between the flush handle and the outside, front wall of the toilet tank must be made great enough to accommodate all the external structures, as may best be seen for the Flush Light™ in FIG. 8 of 10/967,227, op. Cit., reproduced here in FIG. 10. Yet it is simultaneously desirable to keep the Flush Light™ as close as possible to the external tank wall, in the manner of conventional flush handles, in order to accommodate the occasional toilet whose tank lid is missing. When a tank lid is missing, a toilet's seat will lean back right against the tank itself. The farther a flush handle extends out from the tank's external wall, the more likely will the flush handle be to come into contact with a leaned-back seat, when a tank lid is missing. The present invention minimizes this possibility.

Side-mounted flush handles never, of course, are exposed to the hazard of contact with a leaned back seat. However, side-mounted flush handles, relative to front-mounted handles, make up only a fraction, perhaps between 5 and 8 percent, of the already installed, old-for-new, flush-handle exchange market. Furthermore, side-mounted flush handles may be more challenging for toddlers, the aged, and the handicapped to reach. Side-mounted flush handles thus do not lend themselves readily to enhanced functions. For these reasons, the present discussion focuses on front-mounted handles, although the present invention's application is not limited to front-mounted handles.

SURVEY OF BACKGROUND ART

U.S. Pat. No. 3,278,948 to Jensen (1964) discloses an invention superficially similar to the present invention, but lacking the present invention's ease of mounting to a toilet tank. According to Jensen, column 2, lines 31-54, Jensen's flush lever must be stepwise assembled subsequent to his “bushing 6” and “lock nut 14” first having been attached to each other through the wall of the toilet's tank. If this is not done, if, instead, Jensen's “arm 28” has first been secured to his “shaft 24” and his “shaft 24” has in turn been passed through “bushing 6” and been secured in “operating handle 40,” then Jensen's “lock nut 14” will not be able to pass over his “arm 28” and onto his “bushing 6,” and thus Jensen's invention will not attach to a toilet tank. Jensen's invention, furthermore, requires that an installer endeavor to align “openings 32 which register with opening 26 for reception of pin 34,” see column 1, lines 71-72. But these parts are all rather small for the average man's hand and/or will be difficult to align if a person's eyesight and/or the lighting is less than good. Moreover, should one of these little metal parts, such as “pin 34,” drop onto the floor and bounce, it may be lost. In terms of ease of assembly, Jensen's invention represents a step backward from the convenience of earlier flush handles, such as U.S. Pat. No. 2,609,546 to Gulick (1952).

U.S. Pat. No. 1,675,248 to Campbell (1927) is likewise superficially similar to the present invention and is happily less complex than Jensen's. Nonetheless, and like Jensen's, Campbell's invention also requires the inconvenience of a multi-stage assembly: first of its “bearing member” with its “clamp nut 10,” lines 76-82, and then of its “handle 11” with its “spindle 3” by means of “screw 4,” lines 85-90. Additionally, Campbell's “bearing member” must be held by an installer firmly with one hand while the installer with the other hand starts to thread “clamp nut 10” over it. If Campbell's “bearing member” is not firmly held, it may slip and fall into the water of the toilet tank. For that same reason, Campbell's “lever 2” needs to be held while “screw 4” is threaded into its end. Nor can Campbell's invention borrow from Jensen's in order to use Jensen's “lock nut 14” to secure Campbell's “bearing member” from within the tank, because to do so first would require destroying the architecture of Campbell's “bearing member.”

Neither the “bearing member” of Campbell nor “bushing 6” of Jensen has a rear wall by means of which to help distribute and absorb the stress of intercepting their respective lift arms during flushing, repeated over days and years.

U.S. Pat. No. 2,320,912 to Crampton (1942) has a “threaded stem 9” that, unlike Jensen's “bushing 6,” does not resemble the present invention at all. However, Crampton does appear to show a little structure extending from his “intermediate rocking section 11,” column 2, lines 40-45, which structure superficially resembles an element of the present invention. But Crampton's “stop projection,” mistakenly numbered 11 in his text, does not limit rotation, rather it limits translation: it “holds the mounting sleeve fixture against movement lengthwise of section 11 which passes therethrough.” Crampton's actual means for rotation limitation is his “lug 5” captured within his “recess 10,” see FIG. 3 and column 2, lines 22-28. But both his “lug 5” and his “recess 10,” however, are on the external side of the toilet tank. Nor can Crampton's “stop projection” be borrowed by Jensen in order to limit Jensen's rotary motion, without first destroying Crampton's invention, because all of Crampton's movable structures, including his “stop projection,” are integrally formed from a single “metallic rod”—see Crampton, column 1, line 47, to column 2, line 5.

In short, Jansen cannot be combined either with Campbell or Crampton to arrive at the present invention. Campbell's and Crampton's teachings lead away from the present invention, and in fact their inventions first must be destroyed before their inventions' elements can be cannibalized for use. But exactly such destructive alteration forms the basis of the inventive process, and the inventive step.

BRIEF SUMMARY OF THE INVENTION

The present invention moves the contemporary, conventional means for motion limitation from outside to inside the toilet tank, meanwhile providing for the attachment of the entire flush handle assembly, including its lift arm, in a single operation with a conventional, left-handed hut. The present invention accomplishes these goals by providing a lift arm comprising a bent portion having an extension adjacent to the spud of sufficient length to permit the conventional, left-handed nut to slip over that extension and onto the spud's threads while simultaneously equipping that extension with an integrally formed, radial projection that is captured rotationally between the walls of a cutout both in the cylindrical sidewall and in the planar rear wall of the spud. By involving the rear wall of the spud and not merely the sidewall, the present invention greatly increases the durability of the mechanism compared to exclusive sidewall involvement, as in Jensen. In the preferred embodiment of the present invention, all of the component parts are plastic injection molded from tough resins such as nylon, abs, or acetal. Where gluing is required during factory assembly, the parts are preferably made of abs.

Some-important objects of the present invention are thus

• 1) To provide a toilet flusher comprising an external, readily detachable flush handle and internal plastic lift arm, wherein the external flush handle is located as close as to the external surface of the toilet tank as a conventional, non-detachable flush handle normally would be located and that can be installed in a single step.
• 2) To provide a toilet flusher comprising an external, enhanced-function flush handle, an intermediary connecting element, an internal plastic lift arm, and a spud wherein the connecting element and the lift arm rotate, but are limited in their-rotation by structurally durable adaptations both of the spud and the lift arm.
• 3) To take two, unremarkable, household objects, a toilet-flusher lift arm and spud, and give to each an altered function and new look, thus to intrigue and attract customers.

These and still-further objects and advantages of the present invention will become apparent from a consideration of the following drawing, detailed description, and appended claims.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

Referring to the drawing, wherein like reference characters indicate like parts or elements throughout the several views, and wherein arrowheads indicate physically-composite objects whose numbered resolution into constituent parts occurs only when it is germane to the discussion:

FIG. 1 is a partially broken away, oblique, perspective view, taken from above and substantially behind, of the present invention attached to a conventional toilet tank and connected to an enhanced function flush handle in its at-rest, horizontal position.

FIG. 2 is an enlarged, oblique perspective view taken from above and substantially in front of one element of the present invention.

FIG. 3 is a front, plan, partial, broken away view of the element of the invention shown in FIG. 2, enlarged in scale and taken along line 3-3 of FIG. 2.

FIG. 4 is an oblique, perspective view of the present invention connected to two related parts, taken from above and substantially toward one end of the present invention and in the scale of FIG. 2.

FIG. 5 is an oblique, perspective view of one element of the present invention in engagement with one of the two related parts shown in FIG. 4, and taken substantially toward one side and doubled in scale relative to FIG. 4.

FIG. 6 is an enlarged view of the elements of the present invention enclosed within box 6 in FIG. 4, the scale being that of FIG. 5.

FIG. 7 is a rear plan view of the elements shown in FIG. 5 approximately 1.25 times the scale of FIG. 4.

FIG. 8 is a rear plan, partial broken away view of the present invention shown in FIG. 4 taken along line 8-8 and approximately 1.25 times the scale of FIG. 4 and with the connected external structures shown in FIG. 1 partially broken away and the connected internal structure shown in FIG. 1 omitted.

FIG. 9 is a view of the elements of FIG. 8 rotated away from their at-rest position, shown in FIGS. 1 and 8, as far as they will go.

FIG. 10 reproduces FIG. 8 of 10/967,227, op. Cit., minus the number lines and numbering, and below it places an identical side view of the present invention likewise connected to the same toilet-tank wall, and with actual dimensions shown for comparison.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

FIG. 1 shows toilet tank 11 to which Flush Light™ 20 comprising battery 22, battery snap clip 23, and housing 21 is attached by threaded spud 40 and nut 30. Flush Light™ 20 is in its at-rest, horizontal position. Extending into tank 11 from the end of spud 40 is plastic lift arm 400. As drawn, Flush Light™ 20 may or may not be removably attached to lift arm 400; however, if it is removably, rather than permanently, attached, then an element called “tenon 300” in 10/967,227, op. Cit., will be present, although not visible from the perspective of FIG. 1, into which lift arm 400 will have been permanently glued. Lift arm 400 points down at an angle of about 5° relative to the top of tank 11.

FIG. 2 shows lift arm 400 having top flat portion 423 with a plurality of cut-off notches 426 and bottom flat portion 424 orthogonal to top flat portion 423 and perforated at intervals by a plurality of holes 425. Abutting these elements is weight socket 421 integrally formed with them. The remainder of lift arm 400 comprises weight socket 411 integrally formed with long bi-concave arm 414, bend portion 413, short extension 415, motion limitation hub 450, and shank 440. In actual practice, weight sockets 411 and 421 encapsulate a weight, dovetail into one another, and are glued together. They are the subject of a separate patent application filed simultaneously with the present application. Long bi-concave arm 414 may be bent to conform plastic lift arm 400 to an existing installation. It, too, is the subject of a separate patent application filed simultaneously with the present application.

FIG. 3 shows motion limitation hub 450 in greater detail, in particular shows top flat contact surface 456 and parallel, bottom flat contact surface 457 joined by cylindrical bearing surface 454 and free cylindrical surface 455. Surfaces 455, 456, 454, and 457 are connected by flat forward surface 459. Parallel to surface 459 is flat rearward surface 458 (preview FIG. 6). Short extension 415 terminates in flat bearing surfaces 416 and 417, which are coplanar with rearward flat surface 458.

FIG. 4 shows tenon 300 by means of which, and in the manner disclosed in 10/967,227, op. Cit., Flush Light™ 20 is removably connected to lift arm 400. As shown in the present application, tenon 300 looks a bit different from the tenon 300 shown in 10/967,227, but the differences are not material to the present invention, nor to the substance of 10/967,227. Lift arm 400 and tenon 300 are permanently joined. Indeed, lift arm 400 and spud 40 are inseparable, regardless of whether lift arm 400 is joined permanently to Flush Light™ 20 or is permanently joined only to tenon 300 to which Flush Light™ 20 is then removably connected. We see again motion limitation hub 450, short extension 415, bend portion 413, long bi-concave arm 414, and the other, already enumerated elements of lift arm 400.

FIG. 5 provides a detailed look at spud 40. Flange 43 is about 1/16″ thick and is the only, physical separation between housing 21 of Flush Light™ 20 and the external front surface of tank 11, with the exception of a very narrow, anti-rub air gap of about 0.01″ between housing 21 and flange 43 after Flush Light™ 20 has been engaged with tenon 300. Realistically, flange 43 should not be made appreciably thinner than 1/16″ because flange 43 supplies the needed resistance to effect a tightening of nut 30, which in turn secures the mechanism of FIG. 4 to tank 11. Square portion 42 keeps spud 40 from turning in the square hole in tank 11 through which spud 40 is inserted. Behind square portion 42 is a left-hand threaded cylindrical portion, having left-hand threads 41 and smooth, cylindrical, rear hub 49 with rear wall 48. Spud 40 has a uniform, axial, cylindrical counterbore extending through it up to rear wall 48, and forming interior cylindrical surface 491 parallel to the external, cylindrical surface of hub 49. A rounded wedge is cut from hub 49 including from rear wall 48, in order to create flat bearing surface 45 parallel to flange 43, cylindrical bearing surface 44 concentric with cylindrical hub 49, and flat contact surfaces 46 and 47 at the sides of the wedge. Cylindrical shank 340 on tenon 300 extends into the counterbore in spud 40 and has a diameter slightly less than cylindrical surface 491, allowing shank 340 to rotate freely within spud 40. Shank 340 has complex axial bore 341 into which shank 440 of lift arm 400 is permanently cemented. Tenon 300 has been oriented vertically in FIG. 5 so that, after spud 40 has been attached to tank 11, as in FIG. 1, side wall 301 is parallel to the vertical faces of square portion 42 of spud 40. With tenon 300 so oriented, Flush Light™ 20 will be horizontal.

FIG. 6 demonstrates that flat forward surface 459 may bear upon surface 45 but that the radius of free cylindrical surface 455 is slightly less than the outer radius of rear hub 49, so that cylindrical surface 455 is stepped back a bit from the edge of flat surface 45. As a result, nut 30, which has hexagonal faces 31 and flange 32, fits comfortably around bend portion 413, and over short extension 415, then over rear hub 49 and onto threads 41 without making contact with motion limitation hub 450. Flat bearing surfaces 416 and 417 (review FIG. 3) bear upon rear wall 48, and cylindrical bearing surface 454 bears on cylindrical surface 44 of rear wall 48 of hub 49 (review FIGS. 3 and 5). Counterclockwise rotation (always as seen from the user's perspective in front of tank 11) of lift arm 400 is limited by surface 46 of spud 40 when surface 46 makes contact with surface 456 of hub 450. Clockwise rotation of lift arm 400 is limited by surface 47 of spud 40, when surface 47 makes contact with surface 457 (review FIG. 3) of hub 450.

FIG. 7 shows spud 40 and tenon 300 end on and from the rear, showing in particular that non-circular bore 341 in tenon 300 has at least one plane of symmetry inclined 5° relative to the vertical sides of tenon 300.

FIG. 8 shows Flush Light™ 20 in its horizontal, at-rest position, with lift arm 400 inclined downward at 5°, as in FIG. 1. Surface 457 of motion limitation hub 450 of lift arm 400 is in contact with flat contact surface 47 of rear hub 49 of spud 40. As seen from the outside and in front of tank 11 (FIG. 8 is a view from behind and inside the tank), surface 47 prevents any further clockwise rotation of Flush Light™ 20, and thus maintains Flush Light™ 20 in its horizontal, at-rest position. The conventional water valve to which lift arm 400 is made to be attached, usually by some sort of bead or link chain, will always lie below Flush Light™ 20 relative to the top of tank 11. To help to keep some slack in the chain, and thus to help keep the water valve closed and less likely to leak, lift arm 400 is given a slight downward bias in its at-rest position, as depicted in FIGS. 1 and 8. The downward bias is achieved by the slight tilt (as shown in FIG. 7, where it is 5°) of a plane of symmetry of non-circular bore 341 relative to the side walls of tenon 300, combined with the orthogonal, non-tilted, alignment of that same plane of symmetry relative to surfaces 456 and 457 of shank 440 of motion limitation hub 450 (review FIG. 3). Shank 440 is cross-sectionally similar to bore 341.

FIG. 9 shows Flush Light™ 20 after being given the usual downward push to flush the toilet to which it is attached. In fact, Flush Light™ 20 is shown to have been rotated as far counterclockwise (recall that FIGS. 8 and 9 are views from inside the tank), as it will go. On its own, lift arm 400 will typically be designed to rotate through an arc that can bring it to something like 25° or so above the horizontal. However, in actual practice, the chain connecting lift arm 400 to a particular water valve will rarely allow such a wide swing, nor will the tank lid. The underside of the tank lid will typically not lie very far above the rim of the tank. In FIG. 9, tank 11 has a rim that clearly will lie well below the far end (not shown) of lift arm 400. Counterclockwise, flushing rotation thus will usually not first be limited by the contact of surface 456 of motion limitation hub 450 with surface 46 of rear hub 49.

FIG. 9 with FIG. 8 show that flat contact surfaces 46 and 47 of rear hub 49 of spud 40 are orthogonal to the plane of bearing surface 45 and include between them an acute angle, which is the range of angular motion of lift arm 400. Flat contact surfaces 46 and 47 each involve rear wall 48 of spud 40 and the cylindrical side wall of spud 40, the cylindrical side wall having both threaded and un-threaded portions, the un-threaded portion adjacent to rear wall 48 being just the cylindrical side wall of rear hub 49.

FIG. 10 compares the ability of the present invention to keep Flush Light™ 20 as close as possible to toilet tank 11 with the same ability of the means of rotation limitation disclosed in 10/967,227, op. Cit. The dimensions shown are based on actual prototypes; indeed FIG. 10, at least as filed, is drawn life size. The present invention keeps Flush Light™ 20 about 0.11″ (=1.333″-1.223″, or about 10% of its overall width of 1.108″) closer to tank 11 than the motion limitation means disclosed in 10/967,227, a significant improvement.

Inasmuch as modifications and alterations apparent to one skilled in the art may be made to the herein described embodiments of the present invention without departing from the scope and spirit thereof, it is intended that all matter contained herein be interpreted in an illustrative, and not in a limiting, sense with respect to the invention claimed in the following claims and equivalents thereto.

Claims

1. A toilet flusher comprising a flush handle, a spud, and a lift arm, said toilet flusher being adapted to transmit motion to said lift arm when said toilet flusher is attached to the water tank of a toilet and said flush handle is actuated by a person, said motion having a limited range and being sufficient within said limited range to flush said toilet, said lift arm comprising a motion limitation hub, said spud comprising a rear hub having a side wall and a rear wall, said side wall and said rear wall being adapted to engage said motion limitation hub of said lift arm such that said motion of said lift arm is limited by said engagement to said range of motion.

2. A toilet flusher as in claim 1 wherein said motion is a rotary motion.

3. A toilet flusher as in claim 2 wherein said rotary motion has an axis of rotation and said spud has a cylindrical counterbore, and wherein said axis of rotation is substantially coincident with the axis of said cylindrical counterbore.

4. A toilet flusher as in claim 1 wherein said rear wall has a cylindrical bearing surface and said motion limitation hub has a cylindrical bearing surface in engagement with said cylindrical bearing surface of said rear wall.

5. A toilet flusher as in claim 1 wherein said rear hub has two flat surfaces orthogonal to the same plane, said two flat surfaces including between them an acute angle, and each of said two flat surfaces involves both said side wall and said rear wall of said rear hub.

6. A toilet flusher as in claim 1 wherein said rear hub has a cylindrical external surface and said motion limitation hub comprises a plurality of cylindrical surfaces parallel to said cylindrical external surface of said rear hub, but wherein the radius of each cylindrical surface of said plurality is less than the radius of said cylindrical external surface of said rear hub.

7. A toilet flusher as in claim 1 wherein said means for limiting said motion of said lift arm comprises a flat bearing surface, and said lift arm has a motion limitation hub having a flat bearing surface in engagement with said flat bearing surface of said means.

8. A toilet flusher as in claim 7 wherein said flat bearing surface limits the translational motion of said lift arm.

9. A toilet flusher comprising a flush handle, an externally threaded spud, an internally threaded nut capable of threaded engagement with said spud, and a lift arm, said lift arm being inseparable from said spud, said toilet flusher being adapted to transmit motion to said lift arm when said toilet flusher is attached to the water tank of a toilet and said flush handle is actuated by a person, said toilet flusher having a means for limiting said motion of said lift arm, said motion of said lift arm being limited to a range of motion and being sufficient within said range to flush said toilet, said means for limiting said motion of said lift arm being located entirely within said tank when said toilet flusher is attached to said tank, said lift arm having a portion extending from said spud and into the interior of said tank, and said portion of said lift arm can pass through said nut such that said nut can be brought into threaded engagement with said threaded spud.

10. A toilet flusher as in claim 9 wherein said motion is a rotary motion.

11. A toilet flusher as in claim 10 wherein said rotary motion has an axis of rotation and said spud has a cylindrical counterbore, and wherein said axis of rotation is substantially coincident with the axis of said cylindrical counterbore.

12. A toilet flusher as in claim 9 wherein said means for limiting said motion of said lift arm comprises a cylindrical bearing surface, and said lift arm has a motion limitation hub having a cylindrical bearing surface in engagement with said cylindrical bearing surface of said means.

13. A toilet flusher as in claim 9 wherein said means for limiting said motion of said lift arm comprises two flat surfaces orthogonal to the same plane, said two flat surfaces including between them an acute angle.

14. A toilet flusher as in claim 9 wherein said means for limiting said motion of said lift arm comprises a flat bearing surface, and said lift arm has a motion limitation hub having a flat bearing surface in engagement with said flat bearing surface of said means.

15. A toilet flusher as in claim 14 wherein said flat bearing surface limits the translational motion of said lift arm.

16. A toilet flusher as in claim 9 wherein said lift arm has a bend and a motion limitation hub, said bend being joined to said motion limitation hub by an extension integrally formed with said bend and said motion limitation hub.